Generally speaking, the use of metal in an aquarium should be avoided. Low doses of copper are often used as a treatment for specific aquarium diseases, but too much can become toxic to fish and other aquatic animals.

Bettas are pretty hardy animals, but enclosed in one of those very tiny betta bowls with a plant on top and copper wire leaching traces into the water... it might end up poisoning your fish eventually.

I'd recommend instead using plastic ties. Perhaps those cable ties or fishing line. Generally, plastic is safe for aquarium use but metal is not.

Hope this helps. =)

Thanks, and don't worry - he's not in a tiny bowl (barbaric!), and in fact is going into a small tank with filter, heater, etc. very soon. The reason for the copper was to suspend the plant with only the roots in the water, but it was necessary for the wire to meet the water to do it. But you're right, plastic's better.

Awesome! Sounds like a fun setup! Don't mind me, I've just seen far too many of those betta & plant packages in a 1/2 gallon jug... it's pretty sad. :P

Good luck with the tank! =)